A slaked lime-based plaster material or a plaster is made by kneading the slaked lime adding fibers of seaweeds such as red seaweeds (Rhodophyts), Chondrus, Gigartina, Iridaea and the like as a putty with water, and is a building material applied for wall, roof, and fence and the like by using trowel since ancient times.
Specific seaweeds in the natural seaweeds such as red seaweeds (Rhodophyts), Chondrus, Gigartina, Iridaea which are used for putty materials, are added to slaked lime after dissolved with hot-water and kneaded with added water, then the seaweeds make slaked lime putty spread and improve workability, and after coating, fix carbon dioxide gas in the air, and cure while producing calcium carbonate so that performances such as adhesive properties to bases, surface hardness, cracking resistance, and water resistive properties are made to improve.
Also, recently the ready-mixed type which is prepared by the previous compounding of the base material, putty material, and fibers and the like is preferably used, in considering to the labor cost saving, efficiency of work, and stability of quality in a construction site. In these circumstances, as putty material, powdered red seaweeds which are prepared by the above mentioned seaweeds which are boiled, dried and powdered, or water soluble powdered materials such as methyl cellulose or cellulose derivatives are applied. Without gelating in the alkaline region, these materials provide effectiveness to the adhesive properties to bases, water holding, viscosity control, workability, and reinforcement of surface hardness with a small quantity of addition.
Meanwhile, since the present living environment pursues labor and cost savings, ply wood, paper wall and resin based painting are frequently applied. As a result, volatile organic solvents including formaldehyde generate a cause of sick house syndrome by vaporizing in rooms.
Under such circumstances, natural building materials and inorganic-based materials are reviewed. Especially, since plasters and the like can provide specific massive feeling and posh feeling by thick-coating and three-dimensional pattern finishing, a various expression of designs are possible and additionally since plasters have environmental purification functions such as air clean-up properties, humidity conditioning properties, mildew resistive properties and the like, they are regarded as building materials of “symbiosis housing”.
However, the above mentioned natural seaweeds that can not be used directly, are applied after dissolved in water, and because of insolubility in cold water, after being dissolved by boiling to remove insoluble materials, then they are added to a slaked lime-based and the slake lime-based putty having adequate workability and viscosity is obtained by adjusting blend water quantity. Moreover, by reason of a large quantity of impurities even after boiling, problems remain such as low level solubility, removal of insoluble portion, peculiar strong odor, and incapability of storage by perishability.
Also, since powdered red seaweeds which are made from the natural seaweeds by drying and powdering, contain a large quantity of impurities, water solubility is in low level, and when powdered red seaweeds are compared with the case of red seaweeds putty extracted by hot-water, the effect is difficult to be revealed.
Meanwhile, water soluble powder materials such as methyl cellulose and cellulose derivatives are superior in water holding and viscosity control properties of slaked lime-based putty but by reason of excessive high stickiness properties, trowel release properties become inferior when coating by trowel work and flat coating with uniform thickness is difficult. Moreover, after coating, since there are disadvantages such as water resistive properties of cured material, for example, occurrence of de-lamination and cracking with base surfaces, by a repeat of wet by rain and dry, water soluble powder materials are faced with problems compared with the natural seaweeds.
The object of the present invention is to provide plastering compositions furnished for the performances for slake lime-based plaster materials.